Lignocellulosic feedstocks (e.g. lignocellulosic biomass) comprise mainly cellulose, hemicelluloses, and lignin. Lignocellulosic feedstocks typically are obtained from renewable resources, such as agriculture, forests, and refineries associated therewith and are not considered to be food sources. In view of these aspects, lignocellulosic feedstocks are considered desirable for the production of biofuels, chemicals, and polymers.
Some existing methods for processing biomass delignify lignocellulosic feedstocks using solvents or other chemicals prior to hydrolyzing the cellulose. In such delignification processes, complex equipment typically is required and is expensive to operate because of solvent or chemical usage. In other existing processes, the conversion of lignocellulosic biomass in pre-treatment or hydrolysis steps takes place in the presence of lignin without significant or any delignification steps, and high temperatures typically are employed. At such temperatures, the lignin can be in a glassy state, and, upon cooling, the lignin can agglomerate or coalesce into one or more large masses that are difficult to work with. Additionally, without suitable control of the conditions upon cooling (e.g., temperature and agitation), the apparatuses employed can also foul, requiring the biomass processing operations to be shut down for cleaning.
There continues to be a need for providing an improved method of coalescing a substance (e.g., lignin derived from a lignocellulosic biomass) into a form that is easier to manage and without substantially fouling the equipment employed.